nvwgf2umx.dll crash sometimes

I've seen some other posts on the inteet about this error, but none of the solutions have worked for me. After some time playing Dark Souls III (5-6 min), the game crashes in the DLL nvwgf2umx.dll according to Event Viewer. Here are the things I've tried:

• sfc /scaow -- found some corrupted files and claimed to have successfully replaced them
• Clean install of NVIDIA's 368.69 drivers from the website
• Full reinstall of Dark Souls III via Steam

I'm ruing two 980 Tis in SLI at 4K with GeForce Experience recommended settings. The temps near the crash max out at 84C according to GPU-Z, but ruing Furmark fullscreen at native resolution for 20 minutes does not reproduce the crash at the same temperatures (although the GPUs do throttle down from 70+ fps to 52ish).

I've also been getting similar issues in Rise of the Tomb Raider, but not with The Witcher 3. I'm ruing Windows 10 Pro.

What might be the cause of this issue and what can I do to resolve them?